Summary of Work: The BLSA Program in Pulmonary Aging has focused on: A study of longitudinal changes in FEV1 in healthy, non-smoking men and women was reported. Longitudinal analyses of changes in FEV1 were conducted among 91 men and 82 women who had no history of respiratory problems and had never smoked cigarettes. The FEV1 data were modeled using a mixed-effects regression model and longitudinal percentile distributions of FEV1 level were constructed. The findings showed 1) the average longitudinal rate of decline in FEV1 was approximately 240-340 ml/decade in men and women, 2) none of the participants exhibited a sustained improvement in FEV1, and 3) between-subjects variability is greater in men than women and increases with age in men, but decreases with age in women. The age- and gender-specific percentile distributions are the first nomograms which reflect age differences in the variability in pulmonary function. Age associated changes in Maximal Inspiratory Pressure (MIP). Cross sectional analyses of data consisting of 400 men and 295 women ranging in age between 20 and 90 years were done. The average MIP of females across the different age groups was about two thirds that of men. Reference equations for MIP in a healthy subset have been constructed.